Enzyme Function in Metabolism

1. Enzyme Function in Metabolism By: Hina Sardar and ShantaMisir

2. Curriculum ExpectationsSBI3C, Strand B: Cellular Biology • B2.4 investigate the effects of various qualitative factors on the action of enzymes (e.g., the effect of temperature or pH on the breakdown of starch by salivary enzymes) • B3.1 describe the structures and functions of important biochemical compounds, including carbohydrates, proteins, enzymes and lipids

3. Lesson #1: Enzyme Demo • Materials: • apple • lemon wedge • paper plate • Napkin • Procedure: • Have each student take a bite of their apple, and then immediately rub juice from the lemon over the exposed flesh. Be careful not to let the juice touch other areas of the apple. • Each student then takes another bite, on the opposite side of the apple. Do not put any lemon juice on this area. • While the reaction is occurring, the teacher can lecture on what enzymes are, how they work, etc. • After at least a half hour has passed, have the students compare the two bite marks on the apple.

4. Diagnostic Activity • Complete worksheet (see summary sheet)

5. Lesson 2-3: What is an enzyme? What is metabolism? • Students will watch an animation video on Enzymes. • Jigsaw: Divide students in groups, 4 per group. Lay out research materials i.e. Textbook, Computer, Handouts, and Journal Articles etc. Have one student from each group become “experts” on one topic. 1. What is an enzyme? 2. What is Lock and Key Model? 3. What is Metabolism? 4. What factors effect enzyme activity? Group members must come together and educate other members on this topic. • Teacher led discussion on questions provided

6. What is an enzyme? • An enzyme is simply a specialized type of protein that speeds up a certain chemical reaction • 1. Enzymes are specific • 2. Enzymes are catalysts • 3. Enzymes are efficient • 4. Enzymes are natural:

7. What is Lock and Key Model? • In this analogy, the lock is the enzyme and the key is the substrate. Only the correctly sized key (substrate) fits into the key hole (active site) of the lock (enzyme). • Smaller keys, larger keys, or incorrectly positioned teeth on keys (incorrectly shaped or sized substrate molecules) do not fit into the lock (enzyme).

8. What is Metabolism? • Metabolism is the amount of energy (calories) your body burns to maintain itself. Whether you are eating, drinking, sleeping, cleaning etc... your body is constantly burning calories to keep you going. • Discussion: how can enzymes help?

9. Lesson 4: Mind Map + Lab Stations • Students create mind maps on Enzyme Function in Metabolism • Lab Activity follows

10. Lab Stations- Continued • Station 1: What fruits contain enzymes that digest protein? • Station 2: What effect does temperature have on enzyme activity? • Station 3: What effect does pH have on enzyme activity?

11. Lab Safety • Use of goggles • Fire precautions and care handling hot liquids • Safety measures when handling strong acids or base • Proper disposal

12. Student Difficulties/ Misconceptions • Students may experience difficulties understanding the body contains thousands of enzymes, each with a specific substrate and a specific function. • As well, some enzymes are involved in joining two molecules to produce an active molecule, while other enzymes are involved in breaking apart molecules so that it can be taken up by the bloodstream and tissues. • Students may also have difficulty grasping the idea that an enzyme is a protein. Protein is usually seen as an essential dietary requirement that gives the body energy.

13. Solutions • Specific Lock and Key Model Animation to address this concept • Lab Results to demonstrate how enzymes speed up a reaction